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                  <p class="p_Heading1"><span class="f_Heading1">Use Case Diagram</span></p>



  
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                <p class="p_BodyText"><span class="f_BodyText">A </span><span class="f_BodyText" style="font-style: italic;">Use Case</span><span class="f_BodyText"> diagram captures <a href="usecase.htm">Use Cases</a> and relationships between <a href="actor.htm">Actors</a> and the subject (system). It describes the functional requirements of the system, the manner in which outside things (Actors) interact at the system boundary, and the response of the system.</span></p>
<p class="p_BodyText"><span class="f_BodyText">In developing a Use Case diagram, also consider:</span></p>
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<li><span class="f_Bulletlist1"><a href="extensionpoint.htm">Use Case Extension Points</a></span></li>
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<li><span class="f_Bulletlist1"><a href="usingrectanglenotation.htm">Use Rectangle Notation</a></span></li>
<li><span class="f_Bulletlist1"><a href="business_interaction.htm">Business Use Case</a> (stereotyped Use Case)</span></li>
</ul>
<p class="p_SubHeadingL1"><span class="f_SubHeadingL1">Example Diagram</span></p>
<p class="p_BodyText"><span class="f_BodyText">The following diagram illustrates some features of Use Case diagrams:</span></p>
<p class="p_TextIndentedL2"><img src="example%20of%20a%20use%20case%20diagram.png" width="606" height="341" border="0" alt="Example of a Use Case Diagram"></p>
<p class="p_SubHeadingL1"><span class="f_SubHeadingL1">Toolbox Elements and Connectors</span></p>
<p class="p_BodyText"><span class="f_BodyText">Select Use Case diagram elements and connectors from the </span><span class="f_UIControl"><a href="usecasegroup.htm">Use Case</a></span><span class="f_BodyText"><a href="usecasegroup.htm"> pages</a> of the Enterprise Architect UML</span><span class="f_UIControl"> Toolbox</span><span class="f_BodyText" style="font-style: italic;">.</span></p>
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<td valign="bottom" width="955" bgcolor="#efeff7" style="width:955px; background-color:#efeff7;"><p class="p_TiporNote" style="border-top: none; border-right: none; border-left: none;"><span class="f_TiporNote">Tip:</span></p>
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<td width="955" bgcolor="#f7f7ff" style="width:955px; background-color:#f7f7ff;"><p class="p_TiporNoteText"><span class="f_TiporNoteText">Click on the following elements and connectors for more information.</span></p>
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<td valign="top" width="203" bgcolor="#e3e6ed" style="width:203px; background-color:#e3e6ed; border: solid 1px #000000;"><p class="p_Tableheader"><span class="f_Tableheader">Use Case Diagram Elements</span></p>
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<td valign="top" width="207" bgcolor="#e3e6ed" style="width:207px; background-color:#e3e6ed; border: solid 1px #000000;"><p class="p_Tableheader"><span class="f_Tableheader">Use Case Diagram Connectors</span></p>
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